Characterisation of a novel antimicrobial peptide against Helicobacter pylori

About the Project

Applications accepted all year round
Self-Funded PhD Students Only

In our lab, we have discovered a novel antimicrobial peptide which exhibits antimicrobial activity against Helicobacter pylori, the organism associated with the majority of gastric cancers worldwide. With H. pylori classed as a multi-drug resistant organism, it is crucial we act urgently to identify new antimicrobials effective in eradicating infections caused by this organism.

The project aims are to purify the peptide, test its minimum inhibitory concentration (MIC) against H. pylori and analyse its structure. The general hydrophobicity of this class of peptides makes solid phase extraction (SPE) from aqueous to organic phase, such as by C8 or C18 bonded silica, an attractive option for concentrating large volumes of bacterial supernatant. The complexity of whole supernatant extracts requires further, finer purification techniques such as High Performance Liquid Chromatography (HPLC).

Mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) are two tools that in tandem can provide the most complete information about the structural features of this cyclic peptide. For SPE work, the peptide will be eluted from silica beads in increasing concentrations of methanol, the methanol evaporated and the eluates reconstituted in H20 and each tested for bactericidal activity. The fraction exhibiting activity will be further purified by HPLC. Likewise, each HPLC fraction will be tested and the fraction exhibiting activity will be lyophilised and the powder weighed then reconstituted in H20 to make a fixed concentration to establish the MIC. Both Matrix assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray ionization (ESI) MS and NMR will be deployed. The MIC of the structurally characterised peptide will be established.

The student will work in the Biodiscovery Institute at the University of Nottingham where the supervisory team of academics is based. They will benefit from the expertise of a multidisciplinary team of microbiologists. The student will be trained not only in the relevant laboratory techniques but in scientific writing and oral presentation. They will participate at annual research symposia to share their findings through poster and oral presentations. Depending on the success of this project, we anticipate the novel antimicrobial progressing to trials. The student will embed mainly in the School of Life Sciences which is home to several hundred PhD students. The University, which is ranked within the top 100 universities globally, provides a wide variety of training opportunities for post graduate students for career development.

The project will last 3 or 4 years and will be (ideally) full time. Home and international students are welcome to apply.